Last week I started using the MinnowBooster market. You can make absolutely crazy returns delegating Steem Power there, but for that reason offers don't last very long, they are snatched up by whales very quickly.
I opened up my own offer at a much lower price and I've been amazed by the level of demand. I did no marketing other than to upvote my post, and I've already delegated several thousand Steem Power via this offer just since yesterday.
Repeat Customers: How to avail of much lower price
Before the 4 week period is up, I will review your voting. If I'm happy that you're a responsible voter I will message you to see if you'd like to continue the delegation. Then to continue it for another 4 weeks, all you'll have to do is transfer Steem at half the new customer rate (so for example, if you paid me 2 Steem for 100 Steem Power, you would only have to send 1 Steem to get the 100 Steem Power for another 4 weeks).
You can also message me to increase the amount in a repeat period. I will set a maximum of double the previous Steem Power to avail of the repeat customer price.